The UCSF Immunology Training Program encompasses 46 laboratories engaged in molecular, cellular, and in vivo immunology and actively training ~250 graduate and postdoctoral scientists. Areas of active research include many areas of contemporary immunology such as lymphocyte cell surface receptor function and mechanisms of signaling; mechanisms of innate immune recognition; lymphocyte and leukocyte cell biology, adhesion and migration; cytokine expression and in vivo function; CD4 T cell effector and regulatory function; cytotoxic T cell and NK cell function; microRNA regulation of immune cell function, lymphocyte development, hematopoiesis and their relationship to leukemia and lymphoma; in vivo mechanisms of autoimmunity, allergy, and inflammatory diseases; human immunodeficiency; and immune defense against infectious agents including malaria, Histoplasma, Tuberculosis, and HIV. Over the past 29 years, a vital graduate training program leading to the Ph.D. has been developed by the immunology program faculty and has been supported by this training grant for the past 25 years. This program is designed to provide a solid background in genetics, cell biology, molecular biology, and mammalian tissue and organ biology as well as thorough training in modern immunology. The interdisciplinary nature of this training is enhanced by the affiliation of the Immunology Program with the UCSF Biomedical Sciences Program (BMS), an interdisciplinary program that also includes the study of infectious agents and inflammatory processes as well as other aspects of mammalian tissue/organ development, function, and disease. In addition to formal coursework and thesis research, the Immunology Program includes an active weekly seminar series of outside immunology speakers, both Immunology and BMS student-faculty journal clubs, an annual Immunology Program Retreat (held jointly with UC Berkeley immunologists), and seminar courses on advanced immunological topics. These activities provide an excellent training environment for postdoctoral fellows as well as for graduate students. Postdoctoral training is additionally enhanced by a postdoc research-in-progress seminar series and a recently developed postdoctoral mentoring program.